Bentonite greases



Patented Jan. 20, 1953 UNITED QEFl C-Ei BENTONITE GREASES NoDrawing.Application December 24, 1949, Serial No. 135,036

4 Claims. 1

This invention relates to.a new and improved lubricating com-position.Particularly, theyv invention relates to a lubricating composition,which comprises. a. synthetic. oil thickened to; a. grease consistencywith an. organophilic bentonite. More particularly, the, invention.relates. to a grease composition prepared: by dispersing; in a syntheticlubricating oil a complexreaction product formed by reacting a bentonititypeclay with an aliphatic amine salt.

The complex products formed by reacting bentonitic or montmorillonitictype clays with aliphatic amine salts are known in the art. of thesecompounds are described in U; S; Patent 2,033,856, issued to Smith,March 10, 1936. The swelling of these complexes in organic liquids andliquid mixtures has been observed and a mechanism advancedto accountforthe salvation phenomenon in an article by John W. Jordan in theJournalof Physical Colloid; Chemistry, volume 53, umber-ai' bru rr 1 nbas s 13 -305 inus v Ithas now been found. andforms the subject.

of this. invention that these organophilic bentonites when dispersedin asynthetic lubricating oil form valuable; grease compositions; havingstable properties and excellent high dropping points.

It has been found that forv the most part these organophilic bentonites,particularly those complexesformedbyreacting an aliphatic aminesaltwiththe. bentonite, are dispersible in mineral lu.-

bricating oils. only withextremedifficulty. However, when a syntheticlubricatingoilwhich containsappreciable quantities of long chainalcohols are. used these ,organoph-ilic bentonites are easilyvdispersible. and a. very satisfactory rease composition results.

Although a great'number-of; the synthetic lubricating. oilsare useful,in. manufacturing. the greases of this inventicnthe preferredembcdimentcontemplates. the utilization of the synthetic oilsobtained iromtheso-called OX process. This. process may. be. described as the catalytic,reaction of monoolefins with carbon monoxide and. hydrogen. Attemperatures of about 300 F. to 350? F. and under pressure of about 3Q0pounds. per, square. inch in thepresence oiaoatawstan aldehyde isformed. This aldehyde, is .then hydrogenated to. form. a. primary coholsZmaybe. synthesizedbp this process.- For xamp e a f act on p imer-imco sing; o 1

olefins. which-is isolated from the-polymerization product of propylene,or a migxture oi CcandiCi o oolefi s may e nbiected o he .O oi ro 5.

Somev he .resultinsialcohol .mixturewulbe; found o. have. a m jproportion of fiealcohQliap W a a number of isomers. mm: g mo e l Weightcompounds are. also/ found to be?- present;

From this reaction product,v a. major proportion of which is Ca, OX0alcohol the-- desired cuts are removed by distillation; For example; theC8 OX0. alcohols are distilled ofi. Thebottoms or residuum left afterthis distillation contains a large proportion, of C alcohols, higherboiling alcohols, acetals, esters. ethers and hydrocarbons. In adistillation step the C9, .Oxo alcohols along with anyiother lowboilingmaterials may beremoved. The residuum left. from. this seconddistillation step. represents. ap-proxi mately 33% to 35% of, the.residuev remaining. after the Ca OX0. alcohols, are-removed.

That proportion. of the. product. ofthe. OX0 process remaining after.the. Ca Qxo. alcohol and the C9 Oxo alcohol .cutsare. removedthat' is tosay, that. portionremainingafter the product has beensubjected; tovatem-perature 0fi250 C., are hereinafter referred as to OX0 bottoms andconstitute the preferred synthetic oil operable in this invention.

Although the. above description isispecifically directed toan OX0.process for the production of a major amountof. Ca Oxo. alcohol; and.the preferred embodiment offthisinvention contemplates theuseof the,bottoms fromthis, particu.- lar process, the.inventi on is notlimitedvtothe. use of these. particular bottoms, The synthetic oils orthe residue remaining after distillation of the mixture ofproductsobtained by subjecting a Wide variety of olefinsto the 0x0processare operable. For-instance, any of .the. variousaolefins'.obtained by polymerizating mixtures. ofi propylenes and. butylenes. maybe. subjected. to: the 0x0 process and the bottomsirom these;proc essesmay be used. In addition, the olefins obtained fromthe hydrocarbonsynthesis reactions may be converted: to Qxo alcohols and? otherproducts and-these bottoms are operable in this invention.

The approximate composition of the residuum boiling above 250 C.is-asfollows Inspection tests on this residuum show-z Flash pointover.3i50 F. Pour point 5;5.? F. S. S. U. viscosity at E 63.13;

Of the organophilic bentonitic materialsioperable in this invention..it. .is .preferredwtos usezthe:

complexes. formed-by reacting .bentonite: with:

aliphatic amino/salt in which the aliphatic contributed portion of theamine has a carbon chain length of from to 18 carbon atoms. Either theprimary aliphatic amine salt or the quaternary ammonium salt may beused. In the case of the latter salt the aliphatic groups may be eitheralike or different, the total number of carbon atoms, however, must bewithin the range of from 10 to 18 carbon atoms.

These organophilic bentonites are normally prepared by adding to a waterdispersion of the bentonite the desired aliphatic amine salt. Thesesalts are normally prepared by reacting the aliphatic amine with thedesired acid. Acetic and hydrochloric acid represent the desired saltforming acids.

In general, the amounts of the organophilic bentonites and the syntheticoil used for the formulation for the greases of this invention are notcritical so long as desired stable grease structure is obtained.However, for most purposes a grease formed of from 10% to 25% of theorganophilic bentonite with 90% to 75% of the synthetic oil results ingreases having optimum stability characteristics and outstandingstructure.

As was mentioned above the formation of the grease composition involvesa. dispersion of the organophilic bentonite in the synthetic oil. Thisdispersion is advantageously accomplished by a milling process. Thismilling step may be accomplished by any of the conventional millingprocedures familiar to the art such as a rolling mill, colloid mill,Lancaster disperser, Manton-Gaulin homogenizer, etc., as long assuflicient shearing action is obtained to give satisfactory dispersion.

This invention will be further explained by examination of the followingexamples.

Emample I Penetration, unworked 300 mm./10.

Penetration, worked (60 310 mm./l0.

strokes).

Penetration, worked (1000 315 mm./10.

strokes) (fine hole worker). Dropping point 500" F.'+'. SolubilityInsoluble in boiling water.

Example II 20% by weight of a complex formed by reactin a quaternaryaliphatic amine salt with bentonite was dispersed in 80% of an Oxobottoms synthetic oil in a manner similar to that described in Example Iabove. Inspection tests on this grease composition gave the followingresults:

Penetration, unworked 250 mm./10.

Penetration, worked (60 260 mm./10.

strokes).

Penetration, worked (1000 2'70 mm./10.

(1000 strokes) (fine hole worker). Dropping point 500 F.+.

Solubility .Insoluble in boiling water.

Example III 15% by weight of a complex formed by reacting bentonite witha primary aliphatic amine salt was admixed with 8%;% by weight of 0x0bottoms. The dispersion thus formed was passed through a standardlaboratory colloid mill with 76.5% by weight of an acid-treatednaphthenic distillate having a viscosity at 210 F. of 55 S. U. S. Theresulting grease composition was subjected to the standard ASTM testsand gave the following results:

Penetration, unworked 290 mm./ 10.

Penetration, worked (60 310 mm./10.

strokes).

Penetration, worked (1000 325 mm./l0.

strokes) (fine hole worker). Dropping point 500 F.+. SolubilityInsoluble in boiling water.

To test the oxidation resistance characteristics of the greasecompositions of this invention a grease similar to that of Example I wasmade incorporating therein 0.5% by weight of phenyl alpha naphthylamine.This grease composition was subjected to the Norma-Hoffman BombOxidation Test and gave excellent results. Operating at 210 F. andpounds per square inch initial oxidation pressure drop was 5 pounds persquare inch in hours.

Although in the preferred embodiment of this invention the dispersant isa synthetic oil obtained from the 0x0 process it is also within theconcept of this invention to use as the dispersant other synthetic oils.Long chain esters, esters of dibasic acids for example sebacates,adipates, and the like, polymers of cracked Wax, alkylated aromatics,polyglycols, copolymers of such materials as diolefins with othersaturates, and other synthetic lubricants known to the art are operablein this invention. Of particular utility among these may be mentioned afluid copolymer of low molecular weight obtained by copolymerizingconjugated diolefins with a minor proportion of an unsaturatedcomonomer. The fluid copolymer preferred is a low molecular Weightbutadiene-acrylonitrile product which is liquid at temperatures as lowas +20 F. to 70 F. This copolymer per se and a preferred method ofpreparation are described in detail in copending application Serial No.637,782, now Patent No. 2,500,983, filed December 28, 1945.

An excellent smooth adhesive grease preparation was manufactured using acopolymer of butadiene and acrylonitrile in which about 76% by weight ofbutadiene was copolymerized with about 25% by weight of acrylonitrile inaccordance with the procedure described in the above mentionedapplication.

15% by weight of a quaternary aliphatic amine salt of bentonite wasadmixed with 85% by weight of the copolymer of butadiene andacrylonitrile by stirring in a grease kettle or other type mixer.Dispersion was thoroughly accomplished by milling on a 3-roll paintmill. The yellow adhesive grease obtained was found to be insoluble inmotor gasoline and petroleum naphthas and gave an ASTM penetration of215 mm./ unworked and a worked penetration (1000 strokes using the finehole worker plate) of 220 mm./10. These penetration tests data show theloss of only 5 mm./l0 after Working which indicates excellent structuralstability.

The grease compositions of this invention may include any of theconventional additive materials such as tackiness agents, viscosityindex improvers, anti-corrosion agents, oxidation inhibitors, extremepressure agents and the like.

In summation, this invention comprises the manufacture of a new anduseful grease composition by dispersing in a synthetic oil obtained fromthe Oxo process an organophilic bentonite complex formed by reactingbentonite with the salt of a long chain aliphatic amine. Either theprimary aliphatic amine or the quaternary aliphatic amine may be used toobtain the salt to react with the bentonite. If the quaternary amine isused the aliphatic groups may be the same or different. The preferredembodiment contemplates the use of hydrochloric or acetic acid to formthe salt with the aliphatic amine.

What is claimed is:

1. A lubricating composition consisting essentially of a syntheticlubricating oil thickened to a, grease consistency with a complex formedby reacting bentonite with an aliphatic amine salt, said syntheticlubricating oil being the residue remaining after distillation at about250 C. of the mixture of products obtained by subjecting a C7 monoolefinto the action of carbon monoxide and hydrogen in the 0x0 process.

2. A lubricating composition consisting essentially of a syntheticlubricating oil thickened to a grease consistency with about 10% to byweight of a complex formed by reacting bentonite with a hydrochloricacid salt of a primary aliphatic amine, said synthetic lubricating oilbeing the residue remaining after distillation at about 250 C. of themixture of products obtained by subjecting a C1 monoolefin to the actionof carbon monoxide and hydrogen in the Oxo process.

3. A lubricating composition consisting essentially of a syntheticlubricating oil thickened to a grease consistency with about 15% to 25%by weight of a complex formed by reacting bentonite with a quaternaryaliphatic amine salt, said synthetic lubricating oil being the residueremaining after distillation at about 250 C. of the mixture of productsobtained by subjecting a C7 monoolefin to the action of carbon monoxideand hydrogen in the 0x0 process.

4. A process for the formation of a new and useful lubricatingcomposition which comprises milling for the desired period of time amixture of about 10% to 25% by weight of a complex formed by reactingbentonite with an aliphatic amine salt with about 90% to by weight of asynthetic lubricating oil, said synthetic lubricating oil being theresidue remaining after distillation at about 250 C. of the mixture ofproducts obtained by subjecting a C1 monoolefin to the action of carbonmonoxide and hydrogen in the Oxo process.

WILLIAM J. SPARKS. ARNOLD J. MORWAY. DAVID W. YOUNG.

REFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 2,033,856 Smith Mar. 10, 19362,248,636 Marsden July 8, 1941 2,260,625 Kistler Oct. 28, 1941 2,467,148Morway Apr. 12, 1949 2,531,440 Jordan Nov. 28, 1950

1. A LUBRICATING COMPOSITION CONSISTING ESSENTIALLY OF A SYNTHETICLUBRICATING OIL THICKENED TO A GREASE CONSISTENCY WITH A COMPLEX FORMEDBY REACTING BENTONITE WITH AN ALIPHATIC AMINE SALT, SAID SYNTHETICLUBRICATING OIL BEING THE RESIDUE REMAINING AFTER DISTILLATION AT ABOUT250* C. OF THE MIXTURE OF PRODUCTS OBTAINED BY SUBJECTING A C7MONOOLEFIN TO THE ACTION OF CARBON MONOXIDE AND HYDROGEN IN THE "OXO"PROCESS.